package shuXue;

public class d01 {
    public static void main(String[] args) {
        double a = -18.56;
        //绝对值
        System.out.println(Math.abs(a));
        //向上取整
        System.out.println(Math.ceil(a));
        //向下取整
        System.out.println(Math.floor(a));
        //四舍五入
        System.out.println(Math.round(a));
    }
}
